I remember using some of those early Windows Mobile gadgets. They were pretty nice and decently capable compared to the rest of the mobile device market at the time. Problems included:
1. UI was stylus-only resistive touchscreen and basically ordinary Windows with a little duct tape to not be too awful on small screens. Still far from good though, and the styluses were clunky and easy to lose.
2. IIRC virtually no custom software and what there was was tough to install, and probably tough to develop too.
3. Web tech just not ready yet for a quality mobile web, not to mention the quality of cellular data and WiFi.
Apple took the market because they were the first to realize and really go all-in on needing finger touch screens and the absolute requirement to make every single part of the UI great to use with fingers. And also hit the market at just the right time for mobile web and cellular data to be just coming into its prime.
Fortunately for Android, they were only a little behind and got the idea on finger-first UIs once Apple showed the way.
Resistive screens have sub-pixel accuracy. First gen capacitative screens recommended UI elements be at least 1cm in size!
Microsoft's bread and butter has been productivity apps for so long, with dense UIs, that I honestly think designing for touch screens just collectively made people's heads explode.
Of course the answer is you don't need all of Excel on a mobile device all the time, but it took Microsoft literally decades to accept this.
Windows Mobile actually had some cool software, and this was back when everyone knew Win32 programming, but iphone had that sweet sweet app store and I'd guess that within a few years the number of ObjC developers grew to be larger than the number of Win32 developers, despite Win32 having almost a multi-decade head start!
Just as an aside, it should be remembered that capacitive touchscreen tech was primitive back then and the more precise resistive touchscreens were preferred to make best use of the tiny screens then available. IIRC, the early iPhones had to have their UI designed to work around the lower accuracy of its touchscreen. On the flipside, it must be said the multi-touch capability that gave it pinch to zoom/rotate really did help with usability.
> "...probably tough to develop too"
Depends on what one considers "tough". Windows CE had most of the Win32 APIs that desktop Windows had, so development was very similar.
1. UI was stylus-only resistive touchscreen and basically ordinary Windows with a little duct tape to not be too awful on small screens. Still far from good though, and the styluses were clunky and easy to lose.
2. IIRC virtually no custom software and what there was was tough to install, and probably tough to develop too.
3. Web tech just not ready yet for a quality mobile web, not to mention the quality of cellular data and WiFi.
Apple took the market because they were the first to realize and really go all-in on needing finger touch screens and the absolute requirement to make every single part of the UI great to use with fingers. And also hit the market at just the right time for mobile web and cellular data to be just coming into its prime.
Fortunately for Android, they were only a little behind and got the idea on finger-first UIs once Apple showed the way.